(closed) Question about Cos & Sin

[degacParticipant]

Hi

I’m playing with MX2, and I decided to do a simple analog clock, porting some old code from BlitzMax.

I’ve a problem understanding why I get different results in just a simple ‘function’ like this one

Monkey

For Local n:Float=0 Until 360 Step 30 canvas.DrawLine(320,240,320+100*Sin(n),240+100*Cos(n)) Next

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For Local n:Float=0 Until 360 Step 30 canvas.DrawLine(320,240,320+100*Sin(n),240+100*Cos(n)) Next

This algorithm should draw a ‘regular’ shape – 12 rays with the same angle.

What’s wrong?

Attachments:

1. 

   clock-mx2.jpg
   

2. 

   clock-bmx.jpg
   

[degacParticipant]

Nevermind

MX2 uses RADIAN, while BMAX degree.

 

Solved & closed!!!

 

Ps: I should have read BEFORE the manual!!!

[ImmutableOctetParticipant]

You’re looking for degrees, Monkey 2 made the switch to radians.

Sin(n * (Pi / 180))

 

Here’s an example of how to convert to and from radians.

Monkey

Function RadiansToDegrees:Double(x:Double) Const RadianScalar:= (Pi / 180.0) ' 57.29577951308232 Return (x * RadianScalar) End Function DegreesToRadians:Double(x:Double) Const DegreeScalar:= (180.0 / Pi) ' 0.017453292519943295 Return (x * DegreeScalar) End Function Cosd:Double(x:Double) Return Cos(RadiansToDegrees(x)) End Function Sind:Double(x:Double) Return Sin(RadiansToDegrees(x)) End Function Main:Void() Print(Sind(10.0)) Print(Cosd(30.0)) End

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Function RadiansToDegrees:Double(x:Double) Const RadianScalar:= (Pi / 180.0) ' 57.29577951308232 Return (x * RadianScalar) End   Function DegreesToRadians:Double(x:Double) Const DegreeScalar:= (180.0 / Pi) ' 0.017453292519943295 Return (x * DegreeScalar) End   Function Cosd:Double(x:Double) Return Cos(RadiansToDegrees(x)) End   Function Sind:Double(x:Double) Return Sin(RadiansToDegrees(x)) End   Function Main:Void() Print(Sind(10.0)) Print(Cosd(30.0)) End

EDIT: Just realized you figured it out.

[degacParticipant]

Thanks

I’m starting from the ‘basis’… so porting old programs/algorithms I think is the best way to understand MX2 and the differences/features.

I’m thinking I need to create a ‘conversion-library’ to manage ‘old’ code (Sind is much better than  Sin(Rad(n))…)

By the way, I think it should be available by default in the Math module some functions for translating from Radian to Degree and viceversa.

[DruggedBunnyParticipant]

Are there any built-in conversion functions? Reckon radians make sense to about 0.000000001% of all humans in comparison to degrees!

[JesseParticipant]

@immutableoctet

I think you got both functions reversed:

Pi/180.0 is not 57.29577….

neither is 180.0 /Pi  =  0.017453….

Monkey

Function RadiansToDegrees:Double(x:Double) Const RadianScalar:= (Pi / 180.0) ' 57.29577951308232 Return (x * RadianScalar) End Function DegreesToRadians:Double(x:Double) Const DegreeScalar:= (180.0 / Pi) ' 0.017453292519943295 Return (x * DegreeScalar) End

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Function RadiansToDegrees:Double(x:Double) Const RadianScalar:= (Pi / 180.0) ' 57.29577951308232 Return (x * RadianScalar) End   Function DegreesToRadians:Double(x:Double) Const DegreeScalar:= (180.0 / Pi) ' 0.017453292519943295 Return (x * DegreeScalar) End

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